Sea Bream Sparus Aurata Linnaeus Research Articles

Farming Sparus aurata (Teleostei: Sparidae) in marsh ponds: trophic characterization and trace metal accumulation

Considering the overexploitation of fishing on most of the world coasts, the ingestion of fish and shellfish will depend mostly on aquaculture production. Since intensive mariculture usually involves environmental impact, developing sustainable cultures is a priority. In this sense, salt marshes can provide ecosystem services and incorporate both conservation and extensive aquaculture activities. In the present study we compared gilthead seabream Sparus aurata Linnaeus, 1758 cultured in extensive and semi-intensive marsh ponds with wild conspecifics from surrounding coastal areas, using trophic characterization (diet analysis and stable isotopes) and trace metal accumulation. Stomach content analysis revealed different feeding habits among gilthead seabream from different origin. Although wild specimens had the most diverse diet, results of stable isotopes showed that extensive diet had the wider isotopic niche and revealed the highest similarities between wild and extensively cultured gilthead seabream. A similar trace element signature was also measured in wild and extensive culture, whereas the semi-intensive culture showed different concentrations for several elements. Cr, Fe and Mn showed the highest concentrations in semi-intensive cultured fish, while As and Zn showed the lowest values in this group. In any case, average values measured in both extensive and semi-intensive culture were, in general terms, below the hazardous limits provided by the standards recommended for trace metals by national and international regulations. Therefore, marsh ponds provide a suitable environment where the cultured fish, especially extensive, should be promoted.

Morphological and molecular characterization of Encotyllabe vallei Monticelli, 1907 (Monopisthocotylea, Monogenea) from the gilthead seabream Sparus aurata Linnaeus (Teleostei, Sparidae) from the southwestern Mediterranean and notes on host specificity of the genus Encotyllabe Diesing, 1850.

Incomplete original descriptions, the unavailability or poor conditions of specimens and the lack of detailed redescriptions have caused the validity of several species of the genus Encotyllabe Diesing, 1850 to be questioned. To date, seven of the recognized species were described upon one or two specimens, hindering study of intraspecific variations. This was made worse by considering few morphoanatomical differences sufficient to erect new species. Among Encotyllabe spp. occurring in Mediterranean waters, E. vallei was first described from the gilt-head bream Sparus aurata (Sparidae) off Italy. Although beautifully illustrated for a paper from that century, morphometric data for E. vallei from the type-host S. aurata remain unavailable. Previous records of E. vallei provided either morphometrical or molecular data, and its validity was questioned. We provide a redescription of E. vallei based on newly collected specimens from the S. aurata from the southwestern Mediterranean (off Algeria) using integrative taxonomy. Analysis of cox1 sequences of E. vallei from S. aurata, compared to sequences from other sparid hosts, mainly Pagellus bogaraveo, revealed a divergence not exceeding 2%, suggesting a stenoxenic specificity for this monogenean. Given that P. bogaraveo is the type-host for Encotyllabe pagelli, we were tempted to suggest a synonymy between E. vallei and E. pagelli. We refrained from doing so because E. pagelli was first described from the Atlantic coast off Brest, France. Morphological data for Encotyllabe from P. bogaraveo are warranted assessing the host specificity of E. vallei and whether there might be a species complex within individual sparid fish species.

Genetic variation of Sparicotyle chrysophrii (Monogenea: Microcotylidae) from the gilthead sea bream Sparus aurata (Teleostei: Sparidae) in the Mediterranean Sea.

The gill monogenean Sparicotyle chrysophrii (Van Beneden & Hesse, 1863) Mamaev, 1984 is a specific and common parasite of wild and cultured gilthead sea bream Sparus aurata Linnaeus, 1758, able to cause disease and mortality in aquaculture systems. Few molecular studies have been carried out on this monogenean, and its population structure and genetic diversity are barely known. This study provides the first contribution to the population genetic variation of S. chrysophrii, based on two molecular markers-the structural ribosomal RNA (rRNA) for the large subunit (28S) and the cytochrome c oxidase subunit I (COI) gene. Samples were collected from the gills of farmed and wild S. aurata from Italy and the Spanish Mediterranean. The analysis included previously published sequences. The 28S rDNA analysis was consistent with previous studies of specimens isolated from S. aurata and confirmed the presence of only one species on the gills of this host in the Mediterranean Sea. The COI sequences analysis suggested that the samples isolated in a previous study from a different host species, wild Boops boops (Linnaeus, 1758) in the Adriatic Sea, may represent a new undescribed sister species of S. chrysophrii. The low nucleotide diversity of S. chrysophrii isolated only from S. aurata versus the high haplotype diversity revealed small differences between haplotypes. The haplotypes shared between wild and farmed hosts from Spain provided the first molecular evidence of the possible transfer of S. chrysophrii between wild and farmed populations of S. aurata. The mtDNA COI analysis did not show a clear genetic structure, probably the result of several factors including coevolution, wild and farmed host interactions, and host population structure in space and time.

The complete mitochondrial genome of the gilthead seabream Sparus aurata L. (Sparidae)

The complete mitochondrial genome of the gilthead seabream Sparus aurata Linnaeus 1758, one of the world’s most important mariculture species, was sequenced using next generation sequencing technology. The genome sequence is comprised of 16,652 bp exhibiting the canonical vertebrate mitochondria gene order. Regions of gene overlap, tRNA length, as well as start and stop codon were similar to those observed in other Sparidae. Phylogenetic reconstructions based on mitochondrial protein coding genes corroborate the view that Sparidae is paraphyletic and includes Centracanthidae.

A survey of viral haemorrhagic septicaemia virus in cultured sea bass and its virulence on juveniles of sea bass, Dicentrarchus labrax (Actinopterygii: Perciformes: Moronidae) and gilthead sea bream, Sparus aurata (Sparidae)

Background. Turkey is one of the major European seed producers of European sea bass, Dicentrarchus labrax (Linnaeus, 1758), and gilthead sea bream Sparus aurata Linnaeus, 1758.  Determination of susceptibility to viral haemorrhagic septicaemia (VHS), a notifiable disease in Europe, is crucial particularly for sea bass and sea bream seed production to develop control measures and to take necessary actions in case of a VHS outbreak.  We hypothesized that VHS virus does not replicate at 16°C and above—the temperature range typical for hatcheries in the Aegean region. Materials and methods. To assess the seasonal occurrence and virulence of viral haemorrhagic septicaemia virus genogroup Ie (VHSV-Ie), a virological survey was conducted in cultured sea bass in the Black Sea. Thirty-five sea bass were sampled monthly from a local marine farm, and examined virologically.  Triplicate groups of juvenile of sea bass (n = 30 per replicate or n = 40 per replicate) and gilthead sea bream (n = 20 per replicate) were challenged by immersion with VHSV-Ie at 12°C and 16°C to determine the occurrence of pathogen transfer and viral replication.  Results. VHSV-Ie, or any other viral pathogen able to infect BF-2 and CHSE-214 cells, did not occur in cultured sea bass of the Turkish Black Sea region. It was impossible to infect sea bass at 16°C but moderate levels of mortality occurred at 12°C. Sea bream, however, were susceptible to VHSV-Ie, presenting low levels of mortality (15%). Conclusion. VHSV-Ie poses no risk to the production of sea bass seed carried out at 16°C and above, but sea bass and sea bream should be monitored for VHSV-Ie where ambient water temperature is below 16°C since the risk of introduction is present. 

Effects of starvation on swimming performance and body condition of pre-settlement Sparus aurata larvae

Body condition in larval fishes is an important determinant of survival in the natural environment. However, few studies correlate body condition with behavioural traits critical for sur- vival, such as swimming performance. In the present study, we compared normally fed larvae of gilt- head seabream Sparus aurata Linnaeus, 1758, at various intervals post-hatch with larvae which were starved for 1 to 3 d (for Ucrit) or 2 d (for swimming endurance). Feeding treatment (fed and or unfed) had no effect on the relationship between Ucrit and larval size. However, in the endurance experi- ment, fed individuals swam twice as far as unfed larvae (19.7 km for fed larvae and 9.5 km for unfed larvae). The RNA/DNA ratio was higher in fed larvae in the Ucrit experiment, but significant effects were only detectable after a 3 d period of starvation. Fulton's condition factor was significantly higher in fed larvae in the endurance trial, which suggests that growth (in weight) of starved larvae was affected by long-term swimming. Taken together, these results suggest that for aging and orientation behaviours (activities in which critical speeds might be involved) are not affected by reduced feeding over a few days, but that sub-lethal effects of starvation may affect dispersal potential (for which endurance swimming is critical) and therefore compromise subsequent recruitment to the adult population.

Sparicotyle chrysophrii (Van Beneden and Hesse 1863) (Monogenea: Polyopisthocotylea) parasite of cultured Gilthead sea bream Sparus aurata (Linnaeus 1758) (Pisces: Teleostei) from Corsica: ecological and morphological study

Sparicotyle chrysophrii infections were highlighted during a parasitological monitoring carried out on cultured Gilthead sea bream Sparus aurata Linnaeus 1758 from aquaculture sites in Corsica. Factors and biological mechanisms regulating parasites populations, particularly controlling the infestation and survival of monogeneans have been studied. Variations in infection support the hypotheses that the main factor determining the infection of S. chrysophrii was temperature and that the parasite life cycle could be influenced by fish size and fish age. One hundred forty-nine of 280 S. aurata studied were infected. Seasonal differences in prevalence of infection were observed in all farms studied. A similar pattern was observed for parasite abundance with maximal infection levels occurring when water temperature were lower. A statistically significant dependence between infection and host size was also observed. The study of the surface topography of S. chrysophrii with scanning electron microscopy highlighted morphological adaptations not previously described. Parasites have developed diverse mechanisms of survival within the host that facilitate the establishment of infection. We mainly studied sensory structures and the anchoring systems of the parasite, i.e., filaments of eggs and haptor, enabling it to ensure the dispersal and survival of the species.

On the first record of a potentially harmful fish, Sparus aurata in the Gulf of California

The record of free and healthy Mediterranean gilt-head seabream Sparus aurata Linnaeus, 1758 in waters of the Gulf of California, Mexico is documented for the first time. Consequences of this introduction are briefly outlined.

Consistency of stress response to repeated handling in the gilthead sea breamSparus aurataLinnaeus, 1758

Gilthead sea bream Sparus aurata Linnaeus, 1758 were subjected to repeated stresses, namely confinement and handling once a month for 5 consecutive months. Plasma cortisol concentration was determined as a primary stress response, and plasma glucose and osmolality, serum agglutination and growth rate were analysed as indicators of the secondary and tertiary effects of stress. The results of the mean values after the five trials showed that most indicators followed a consistent pattern with time. Cortisol and growth rate were positively correlated, and cortisol and osmolality were negatively correlated after stress. Analysis of the individual responses throughout all 5 months showed that 6–20% of the fish displayed a consistently high or low response depending on the parameter analysed.

Structure of monogenean populations, ectoparasites of the gilthead sea bream Sparus aurata

In the Western Mediterranean, the gilthead sea bream Sparus aurata Linnaeus, 1758 is parasitized by two gill monogeneans, Furnestinia echeneis (Wagener, 1857) Euzet and Audouin, 1959 (Monopisthocotylea: Diplectanidae) and Sparicotyle chrysophrii (van Beneden and Hesse, 1863) Mamaev, 1984 (Polyopisthocotylea: Microcotylidae). The spatial structure of these parasitic populations were studied on the French coast in the Gulf of Lions in 1984 and 1985. The relations between the two species forming this guild have been demographically analyses. Their distribution profiles are very similar and display some stability with time, although some increasing trends are perceptible in the spring. These two monogeneans are globally frequent, but always present in only moderate intensities in infrapopulations. Recruitment of F. echeneis is independent of that of S. chrysophrii. This mode of contamination limits massive and simultaneous infestations of a single host, and interspecific competition risks are consequently considerably reduced. Our results suggest these parasites can affect the size of a natural gilthead population to only a limited degree.